并联机器人原文

合集下载

并联机器人综述(英文经典),Parallel kinematics

_______________________________________________________________________________________ Parallel Kinematics 12P a r a l l e l K i n e m a t i c shis document surveys parallel-kinematics literature and identifies its usefulness. Thedocument has been developed while we were developing our SimParallel machine.On of the aims of this document is to propose an effective solution to the limitations of thetwo rotary axes of five-axis machines that are currently used in industry. However, thesurvey of the parallel-kinematics literature will not be limited to this (two DOFs) family ofparallel kinematics mechanisms lest a seed for an idea for our sought mechanism does existin parallel-kinematics mechanisms with other DOFs. The available parallel mechanismsconcepts will be mentioned and then their kinematics usefulness to our purpose will be morecritically stated in the conclusion section.The document consists of the following 11 sub-sections;•Parallel-Kinematics Mechanisms. •Six DOFs Parallel-Kinematics Mechanisms. •Spatial Translational Three-DOFs Parallel-Kinematics Mechanisms. •Spatial Rotational Three-DOFs Parallel-Kinematics Mechanisms. • Other Three-DOFs Parallel-Kinematics Mechanisms.•Asymmetric Parallel-Kinematics Mechanisms. •Two DOFs Parallel-Kinematics Mechanisms. •Four and Five-DOFs Parallel-Kinematics Mechanisms. •Parallel-Kinematics Mechanisms Redundancy. •Parallel-Kinematics Mechanisms in Industrial Machine-Tools. •Summary and Conclusions1. Parallel-Kinematics MechanismsThe conceptual design of PKMs can be dated back to the middle of the last century whenGough established the basic principles of a mechanism with a closed-loop kinematicsstructure and then built a platform for testing tyre wear and tear [Gough, 1956]. A sketch ofthe mechanism is shown in Figure 1. As shown in the figure, that mechanism allowschanging the position and the orientation of a moving platform with respect to the fixedplatform.T______________________________________________________________________________________ Parallel Kinematics 13Later in 1965 Stewart designed another parallel-kinematics platform for use as an aircraftsimulator [Stewart, 1965]. A sketch of that Stewart mechanism is shown in Figure 2. Forsome reason the mechanisms of Figure 1 and that of Figure 2 as well as many variations (e.g.the one shown in Figure 3 ) are frequently called in the literature Stewart platform. They arealso called Hexapod mechanisms.Figure 2 Stewart Platform Figure 1Gough Platform______________________________________________________________________________________Parallel Kinematics 14Of course other mechanisms related, may be less formally, to PKM existed well before andsoon before Gough’s platform. Bonev [2003] surveyed many of these earlier mechanisms.Gough though is the one who gave some formalization to the concept. It might beinteresting to know that Gough’s platform remained operational till year 1998 and it is nowkept at the British National Museum of Science and Industry. See Figure 4 for photos of theoriginal and current shapes of Gough platform.Many have extensively analyzed Gough/Hexapod platform [Hunt, 1983, Fichter 1986,Griffis and Duffy, 1989; Wohlhart, 1994]. One problem with these six-DOFs platforms isthe difficulty of their forward-kinematics solution, because of the nonlinearity and the highlycoupled nature of their governing equations. This difficulty has been overcome byintroducing some assumptions [Zhang and Song, 1994] and a closed-form solutiuon can befound in [Wen and Liang, 1994]. Others introduced some sensors to measure at least one ofFigure 4Old and Revived Gough Platform Figure 3 Gough-Stewart-Hexapod Platformthe variables of the platform and hence reduce the unknowns of the governing equations[Merlet, 1993; Bonev et al, 1999]. The above mechanisms are six DOFs mechanisms becauseeach of them allows the moving platform to move arbitrarily (within the limit of the work-space) in the six DOF space.Having had a look on the mechanisms above one can now introduce a formal definition ofparallel-kinematics mechanisms; A parallel-kinematics mechanism (or parallel manipulator) isa closed-loop mechanism. That is, a moving plate (ie end-effector) is connected to thestationary base by at least two independent kinematic chains, each of which is actuated. Onthe other hand, A serial-kinematics mechanism (or serial manipulator) is an open-loopmechanism in which each link is connected to ONLY two neighbouring links. All themechanisms discussed in the introduction of Chapter 1 are serial-kinematics mechanisms.The advantages of parallel-kinematics mechanisms in general are;•Excellent load/weight ratios, as a number of kinematic chains are sharing the load.•High stiffness, as the kinematics chains (limbs) are sharing loads and in many cases the links can be designed such that they are exposed to tensile and compressive loadsonly [Hunt, 1978]. This high stiffness insures that the deformations of the links willbe minimal and this feature greatly contributes to the high positioning accuracy ofthe manipulator.•Low inertia, because most of the actuators are attached to the base, and thus no heavy mass need to be moved.•The position of the end-effector is not sensitive to the error on the articular sensors.Higher accuracy due to non-cumulative joint error.•Many different designs of parallel manipulators are possible and the scientific literature on this topic is very rich, as will be shown later in this chapter.•The mechanisms are of low cost since most of the components are standard.•Usually, all actuators can be located on the fixed platform.•Work-space is easily accessible.•The possibility of using these mechanisms as a 6-component force-sensor. Indeed it can be shown that the measurement of the traction-compression stress in the linksenables to calculate the forces and torques acting on the mobile platform. This isespecially useful in haptic devices [Tsumaki et al, 1998].On the other hand, the disadvantages of parallel-kinematics mechanisms in general are;•For many configurations there are some analytical difficulties ( eg the forward kinematics solution is not easy or finding all the mechanism singularities can beextremely difficult task).•The need in many cases for the expensive spherical joints.•Limited useful work-space compared to the mechanism size.•Limited dexterity.•Scaling up PKMs can enlarge the translational DOFs and usually is unable to enlarge the rotational DOFs.•Potential mechanical-design difficulty.•Mechanism assembly has to be done with care.•Time-consuming calibration might be necessary. See [Ryu and Abdul-rauf, 2001] to realize that calibration of PKMs is not a trivial issue.______________________________________________________________________________________ Parallel Kinematics 15______________________________________________________________________________________Parallel Kinematics 16Many other different points of view about the benefits of PKMs and their drawbacks can befound in the literature [Brogårdh, 2002].2. Six-DOFs PKMsThe PKMs mentioned in the previous section are six-DOFs PKMs. Some of thesemechanisms have S-P-S kinematics chains. S-P-S chains are preferred as they, as discussed inAppendix A, transmit no torque through the limbs. These PKMs can also be realized usingS-P-U chains or any other chain that has six-DOFs associated with its joints. One can checkthat against Grübler/Kutzbach criterion above, or review Appendix A. In fact acomprehensive attempt to enumerate the joints combinations and permutations that can beutilized when all the limbs are identical has been reported [Tsai, 1998]. It can also be shownthat the DOFs associated with the limbs joints need to be at least six. See Appendix A too.Figure 5 shows one PKM that has been proposed. It uses six P-R-U-U limbs [Wiegand et al,1996]. Similar to the PKMs above this one also has limited tilting ability. The reachabletilting angle changes strongly with the position of the P joints and fluctuates between 20 and45 degrees. In special poses up to 57 degrees can be reached.It is important to notice that changing the number of limbs in symmetrical six-DOFs PKMswill not change the DOFs of the platform. This has been shown using Grübler/Kutzbachcriterion in Appendix A, and also can be observed in Figure 6 to Figure 9. In these examplesthough we need more than one actuator per limb, and if there are less than six actuatorssome of the DOFs will not be controllable.A Symmetrical PKM is one that has identical kinematics chains (also called limbs or legs)each of which utilize identical actuator.Figure 6 shows another six-DOFs PKM [Tsai and Tahmasebi, 1993]. This PKM has three P-P-S-R limbs. However, planar motors can not provide high load-carrying capacity and theyoccupy the whole base leaving no space to the material to be processed. A similar PKM waslater built and studied [Ben-Horin et al, 1996]. Figure 7 shows a PKM with three P-P-R-Slimbs [Kim and Park, 1998; Ryu et al, 1998]. The range of tilting angles of the platform ofthis mechanism is one of the widest that can found in the literature. However, themechanism uses 8 actuators (for the six P joints and two of the R joints) to realize themotion that can be realized with six actuators only, and many translational motions can beFigure 5 Six-DOFs PKM withsix P-S-U limbs______________________________________________________________________________________ Parallel Kinematics 17realized in direct straight lines. A PKM similar to that shown in Figure 7 has been proposedearlier [Alizade and Tagiyev, 1994]. That earlier PKM had three P-R-P-S limbs instead.Figure 6 Six-DOFs PKM with three P-P-S-R chains Figure 7 Six-DOFs PKM with three P-P-R-S chains Figure 8 Six-DOFs PKM using three Scott mechanisms( b ) ( c )______________________________________________________________________________________Parallel Kinematics 18Probably no mechanism is more famous than the single DOF crank-slider of Figure 8.a. It isa P-R-R-R kinematic chain that coverts linear to rotary motion or vice versa. Scott’smechanism of Figure 8.b [Khurmi and Gupta, 1985] is another traditional planar mechanismthat greatly resembles the well known crank-slider mechanism. Three of these Scottmechanisms have been put together, as shown in Figure 8.c, to realize a three-DOFsmechanism and then each of the Scott mechanism was made to displace vertically, resultingin a six-DOFs mechanism [Zabalza et al l, 2002]. Some of the R joints of the originalmechanism have been replaced by S joints to allow spatial motion of the arms. Theadvantage of the concept is that if one attempts to express the position and the orientationof the platform via its three vertices, then the kinematics relations will be fairly decoupled.The PKMs of Figure 6 and Figure 7 could be considered decoupled. Other six-DOFsdecoupled PKMs have also been proposed [Zlatanov et al. 1992; Wohlhart, 1994].Spherical actuators that can provide three-DOFs actuation are expensive and notcommercially available [Williams and Poling, 2000], but if two of these actuators are used theGough-Stewart platform of Figure 3 can be reduced to the one shown in Figure 9. Pendingthe quality and the mechanical characteristics of these spherical actuators, the solution offersan elegant and promising solution. The work-space, as least the translational part of it, is stilllimited though and load is shared between two rather than six limbs.Six-DOFs PKMs represent the roots of the concept of PKMs and hence they had to belooked at. However, one might say that a six DOFs PKM is PKMs at their extreme, andconsequently one might think that reducing the number of DOFs that act in parallel mightalleviate the disadvantages of parallel-kinematics mechanisms while benefiting from theiradvantages. This is actually true in many cases. In trials to avoid the disadvantages of sixDOFs parallel-kinematics mechanisms while utilizing the other benefits of parallel-kinematics mechanisms, two, three, four and five DOFs PKMs were proposed, as will beshown in the subsequent sections.3. Spatial Translational Three-DOFs PKMsThree-DOFs PKMs for pure rotation or pure translation are of special importance as theyare, in our view, represent a low-level entity or building block of PKMs that helps deepeningthe understanding of these mechanisms. One can subsequently hybridize these two buildingFigure 9 Six-DOFs PKM with two S-P-U Chains______________________________________________________________________________________ Parallel Kinematics 19blocks or sub-systems from them. Spatial translational three-DOFs PKMs are discussed inthis section and spatial rotational three-DOFs PKMs are discussed in the next section.Using Grübler/Kutzbach criterion one can see that using three limbs (legs) each having five-DOFs is one way to realize three-DOFs symmetrical PKMs. See Appendix A for examples.Many of such PKMs have been built and Figure 10 to Figure 13 show examples of thisfamily of translational three-DOFs PKMs. That is, Figure 10 shows a PKM with three limbseach with U-P-U joints [Tsai, 1996]. This mechanism has been studied by others [DiGregorio and Parenti-Castelli, 1998] and been further optimized [Tsai and Joshi, 2000] andits mobility also has been discussed in details [Di Gregorio and Parenti-Castelli, 2002].Obviously the same kind of motion can also be obtained using P-U-U kinematic chains[Tasora et al, 2001], as shown in Figure 11.Figure 10 Translational U-P-U PKM Figure 11 Translational P-U-U PKM______________________________________________________________________________________Parallel Kinematics 20One should notice that the U-P-U mechanism is a special case from the R-R-P-R-Rmechanism, when the axes of each R-R pairs are perpendicular. This R-R-P-R-R has beenstudied and the conditions that need to be satisfied to enable its pure translational motionhas been established [Di Gregorio and Parenti-Castelli,1998]. The P joints can also bereplaced by R joints and the result is shown in Figure 12 [Tsai, 1999]. Alternatively one ofthe R joints could be replaced by P joints resulting in R-P-R-P-R (or R-C-C; C forCylindrical) [Callegari and Marzitti, 2003]. This is shown in Figure 13.In fact all the combinations and permutations the basic R and/or P joints that would resultin PKMs with three five-DOFs limbs have been enumerated [Tsai, 1998; Kong andGosselin, 2001]. Notice that if pure translation is sought using symmetrical PKMs, then Sjoints would not be a favorable choice as one S joint in each limb simply means that rotationcannot be constrained.The Delta mechanism [Clavel, 1988] is one of the earliest and the most famous spatialtranslational three-DOFs parallel-kinematics robots, as it has been marketed and usedindustrially for pick and place applications. A sketch of this mechanism is shown in Figure14. This mechanism can provide pure 3D translational motion to its moving platform usingits three rotary actuators via its three limbs. Each of these limbs actually is a R-R-Pa-RFigure 12 Translational R-U-U PKM Figure 13 Translational R-P-R-P-R (R-C-C) PKM______________________________________________________________________________________ Parallel Kinematics 21 (Revolute-Revolute-Parallelogram-Revolute) kinematic chain. The mechanism can alsoprovide a rotary independent motion about the Z axis as a 4th decoupled DOF.Many variations of that Delta mechanism has been proposed and implemented. One ofthese close variations is the patented Tsai’s manipulator [ Tsai, 1997; Stamper 1997 ], whichalso provides 3D translational motion to its platform. Here, the parallelograms areconstructed using R joints instead of S joints and Stirrups in the previous case. Thatmechanism is shown in Figure 15. Another close variation was also presented [Mitova andVatkitchev, 1991]. The kinematic chains of that variation were R-Pa-R-R instead.A P-R-Pa-R with vertical prismatic joints was also suggested [Zobel et al, 1996]. Variationsextremely similar to that were later implemented using pneumatic drives [Kuhlbusch andNeumann, 2002]. These variations are shown in Figure 16.Figure 14Clavel-Delta translational PKMFigure 15Tsai or Meryland translationalPKM______________________________________________________________________________________When the lines of action of the three prismatic joints are tilted further till all of them are inthe horizontal plane, the star mechanism of Figure 17 is then obtained. This mechanism wasdeveloped by Hervé [Hervé and Sparacino, 1992]. Notice here that the prismatic joints arereplaced by helical ones (ie screw & nut), which should not represent a difference fromkinematics points of view.Figure 16Translational P-R-Pa-R PKMs Figure 17 Herve ’ Star translational PKM Figure 18 The Orthoglide translational PKM ( a ) ( b )( c )______________________________________________________________________________________ Parallel Kinematics 23 The orthoglide mechanism [Wenger and Chablat, 2000 and 2002] is another variation withthe angles between the action lines of the prismatic joints are changed further resulting inbetter motion transformation (from joints to platform) quality. This is shown in Figure 18.Prior to that a similar mechanism has also been designed and built as a coordinate-measuring-machine [Hiraki et al, 1997]. In that mechanism the lines of action of theprismatic joints are changed further to guarantee that the heavy parts if the mechanism areresting on the machine base.Parallelograms represent a common thread among the mechanisms of Figure 14 to Figure 18as a parallelogram would directly constrain the rotational motion about certain axis. SeeAppendix A. Notice also that in all the designs above the two axes of the two revolute jointsof each chain are always parallel, sometimes parallel to the direction of the prismatic joint (ifany) and sometimes perpendicular to it, which agrees with conditions shown later in theliterature [Kong and Gosselin, 2004b].It is important to notice that each limb of each of the PKMs of Figure 14 to Figure 18 hasonly four-DOFs associated with its joints. According to Grübler/Kutzbach criterion thesePKMs are not mobile [Stamper, 1997]. In fact some mechanisms are mobile only undersome geometric conditions. These are called internally over-constrained mechanisms. SeeAppendix A for more about these over-constrained mechanisms. Screw theory can beutilized in conjunction with the Grübler/Kutzbach criterion [Huang and Li, 2002] to showthe mobility of these over-constrained mechanisms.Further, other (that do not utilize parallelograms) spatial translational PKMs with three limbseach of which having four-DOFs have been proposed. Symmetrical PKMs that have three(P-R-R-R) limbs and are aimed at realizing pure spatial translational motion have been built[Kong and Gosselin, 2002a; Kong and Gosselin, 2002b]. Two of these PKMs are shown inFigure 19. For these over-constrained PKMs to realize pure translation the followinggeometrical conditions need to be satisfied;• The axes of the 3 R joints within the same limb are parallel.• The three directions of the R joints of the limbs should not be in the same plane orparallel to the same plane.• Within the same leg the axis of the P joint is not perpendicular to the direction of the R joints axes.Figure 19 Translational Over-Constrained P-R-R-R PKMThe directions of the P joints don’t have to be parallel, but if they are this will help enlarging the work-space. Also, it has been shown that if the three directions of the R joints are perpendicular to each other linear isotropic transformations will be obtained throughout the work-space (and thus no singularities). Compare that to the isotropic conditions reported for the orthoglide mechanism of Figure 18. Isotropic transformation is discussed further in Chapter 4.The geometrical conditions of the mobility of a similar over-constrained PKMs that has three C-P-R (P-R-P-R) limbs, shown in Figure 20, have also been found [Callegari and Tarantini, 2003]. These conditions are;•The axes of the 2 R joints within the same limb are parallel.•The three directions of the R joints of the three limbs should not be in the same plane or parallel to the same plane.It has been shown that singularity of that mechanism can be kept outside the work-space while maintaining a convex work-space. The isotropic points of that mechanism have also been shown.Figure 20Translational Over-ConstrainedP-R-P-R Symmetrical PKMIn fact the geometrical conditions of the different over-constrained PKMs that utilize four-DOFs limbs have been enumerated [Hervé and Sparacino, 1991; Kong and Gosselin, 2004a].Using three limbs each with P-P-P joints is actually another, may be trivial, over-constrained translational PKMs.Another concept that has been extensively utilized at the industrial level is presented now. If three limbs each with six-DOFs (eg U-P-S kinematic chain) associated with its joints are used, then the platform will have six DOFs (as discussed in Appendix A). However, if less than six actuators are used with these three limbs then some DOFs will not be controllable.After choosing which DOFs are to be controlled, one can compensate for the known but uncontrolled motion of the remaining DOFs using other, may be serial, mechanism. One can also use some limbs to mechanically constraint some of the platform DOFs. In fact this is the basic idea behind Neumann’s patented mechanism [Neumann, 1988] of Figure 21.This seems like creating some DOFs that are needed and then constraining or compensating for them. Still, the idea has been utilized. Various aspects of this PKM has been studied extensively [eg Siciliano, 1999] and a further utilization of the concept will be shown in a subsequent section of this chapter. One might say or think that this concept/mechanism is actually is under-utilization of resources because of a prior conviction to utilize a Gough-like platform/limbs.____________________________________________________________________________________________________________________________________________________________________________ Parallel Kinematics 254. Spatial Rotational Three-DOFs PKMsExactly as in the case of spatial translational three-DOFs PKMs spatial rotational three-DOFs PKMs can be realized using three limbs each with five-DOFs associated with itsjoints. The difference now is how the joints of the PKM would be assembled. A PKM withthree U-P-U limbs, just like the one discuused in conjunction with Figure 10, has beenproposed [Karouia, and Hervé, 2000]. Another PKM with three R-R-S (or R-S-R) limbs, asshown in Figure 22, has also been proposed [Karouia, and Hervé, 2002a]. PKM with threeR-U-U have also been presented as well [Hervé and Karouia, 2002b]. Figure 23 also showshow to use three P-R-P-R-R (or C-P-U) limbs to realize a spherical/rotation three-DOFsPKMs [Callegari et al 2004]. PKMs with three U-R-C and with three R-R-S legs have beenproposed as well [Di Gregorio, 2001; Di Gregorio, 2002]. A PKM that utilizesparallelograms (similar to the delta PKM above) within its three R-Pa-S limbs was yetanother propsoed spehrical PKM [Vischer and Clavel, 2000]. In fact the possible sphericalPKMs that are based on five-DOFs limbs are enumerated [Kong and Gosselin 2004b; Kong and Gosselin 2004c; Karouia, and Hervé, 2002b; Karouia, and Hervé, 2003].Figure 21 Neumann ’s constrained U-P-S PKM Synthesis of three-DOFs translational PKMs based on either Lie/Displacement group theory [Hervé and Sparacino, 1991; Hervè, 1999] or on screw theory [Tsai, 1999; Kong and Gosselin, 2004a] have been discussed. Figure 22 Orientation R-S-E PKM______________________________________________________________________________________Again, as in the translational case, over-constrained PKMs can be used to realizeorientational PKMs. If only R joints are used then three R-R-R legs can be used [Gosselinand Angeles, 1989]. The geometric condition that will mobilize this over-constrained PKM isthat all the axes of the used R joints are to be concurrent at the rotation center of themechanism. See Figure 24. Figure 25 shows one of these R-R-R limbs separately. Notice thatin this case the space freedom ( λ ) is three as no element of the mechanism is translating,which should simplify the application of Grübler/Kutzbach criterion. Notice also that onlytwo R-R-R legs can theoretically be used to realize a three-DOFs rotational PKM. SeeAppendix A. This is not usually favorable though as one actuator will not be placed on thePKM base. For isotropic transformation the axes of the R joints of each limb should beperpendicular to each other [Wiitala and Stanisi ć, 2000].Figure 24 Orientation R-R-R over-constrained PKM Figure 25 Orientation R-R-R limb Figure 23 Orientation C-P-U PKMWhen P joints are used then four-DOFs legs can be used to realize over-constrainedrotational PKMs [Kong and Gosselin, 2004c]. The combinations and permutations ofpossible over-constrained spherical PKMs as well as their necessary geometrical conditionsare enumerated [Kong and Gosselin, 2004b; Kong and Gosselin, 2004c].As happened in the translational case using Neumann’s PKM of Figure 21, three six-DOFslegs can be used to realize a six-DOFs PKM and then mechanically constrain thetranslational DOFs. The limbs used can have kinematic structure of P-U-S or R-U-S or theirvariations, as per Figure 26. In these cases an arm extending from the base is used topivot/constrain the platform. The P-U-S or R-U-S chains can theoretically be replaced by S-P-S chain, which also has six DOFs associated with its joints [Mohammadi et al, 1993], asshown in Figure 27.( a ) ( b)( c)Figure 26Orientation U-P-S or R-U-S PKMFigure 27Orientation S-P-S PKM______________________________________________________________________________________ Parallel Kinematics 27Type synthesis of three-DOFs rotational PKMs based on either Lie/Displacement group theory [Karouia and Hervé, 2003] or on screw theory [Kong and Gosselin, 2004b] have been discussed.5.Other Three-DOFs PKMsSo far spatial three DOFs mechanisms have been discussed. Three DOFs mechanisms can provide planar motion too. That is, they can provide the platform with two translational motions and one rotational motion about the plane normal. If, one relies on P and/or R joints as well as Grübler/Kutzbach criterion, then one can find that there are 7 possible symmetrical mechanisms. These are (RRR, RRP, RPR, PRR, RPP PRP, and PPR). S and U joints here not useful here. Each of the three identical kinematic chains in this case needs to have 3 DOFs [Tsai, 1998]. Figure 28 [Hunt, 1983] and Figure 29 [Tsai, 1998] represent two of these possible seven mechanisms that have actually been implemented.Figure 28Planar R-R-R PKMFigure 29Planar P-R-P PKMFigure 30Planar PKM with three PRR limbsor redundancyThe mechanism of Figure 30 is another planar symmetrical 3 DOF PKM that has been proposed [Marquet et al, 2001]. Three P-R-R limbs are used. In the figure one can actually see a 4th chain. This is actually a redundant one to treat singularity, which will be discussed in Section 7. With this fourth P-R-R limb P-U-S limbs have also been proposed.Planar PKMs cannot provide two spatial rotational DOFs and hence they can not directly serve the purpose of this work, and hence they are surveyed thoroughly. Other PKMs can ______________________________________________________________________________________。

6PRRS并联机器人关键技术

决策系统应用
决策系统在机器人运动控制、任务执行、人机交互等方面发挥着重要作用，使得机器人能够根据任务需求和环境变化进行自主决策和控制。
6PRRS并联机器人的感知与决策优化
感知与决策优化的必要性
6PRRS并联机器人的感知与决策优化对于提高机器人的运动性能、任务执行效率和自主性具有重要意义。通过对感知和决策系统的优化，可以提高机器人的感知精度、反应速度和控制精度，实现更高效的任务执行和更灵活的运动控制。
6PRRS并联机器人的决策系统
决策系统组成
6PRRS并联机器人的决策系统由控制器、执行器和其他辅助设备组成，用于接收感知系统的信息，根据任务需求和机器人的运动状态，进行决策和控制。
决策系统原理
决策系统根据感知系统提供的信息，结合机器人的运动学和动力学模型，进行任务规划和路径规划，生成控制指令并传递给执行器，实现机器人的运动控制和任务执行。
性能评估与优化
01
根据实际应用场景，建立性能评估指标，并对控制算法进行优
化以提高机器人的运动性能。
鲁棒性改进
02
针对环境变化和不确定性因素，提高控制系统的鲁棒效率优化
03
在实现精确控制的同时，考虑降低能耗和提高效率，以实现绿
色和可持续的机器人运动。
06
6PRRS并联机器人实验与验证
6PRRS并联机器人关键技术
汇报人：日期:
目录
• 并联机器人概述 • 6PRRS并联机器人结构与设计 • 6PRRS并联机器人运动学与动力学 • 6PRRS并联机器人感知与决策 • 6PRRS并联机器人控制策略 • 6PRRS并联机器人实验与验证
01
并联机器人概述
并联机器人的定义与特点
并联机器人（Parallel Robot）

并联机器人_李宇明

LMC101CAA10000 OTB1C0DM9LP TM2DRA16RT TM2DDI16DT TSX CANKCDF90T VW35001S013 LXM52DD12C41000 BMH0702P12F2A VW3M5101R50 VW3M8102R50 减速机 OSMC 32 N3 D10 OSMC 32 N2 C10 OSMC 32 N1 D4
Solution Architecture 施耐德方案架构
Product Package 产品清单
Technical information 技术信息
Experience Sharing 经验分享
Customer Benefit 附件说明
亮点：
• 亮点 1: Sercos III 有着超快的通讯速度,各个驱动器的数据穿过来的速度仅仅在1ms内,这样就等于保证了机器人系统
Schneider Electric - Industry Business – Machine Solutions – Success Stories
5
OTB LXM52 LMC101
BSH
左放卷
皮带
手臂A
手臂B
手臂C
旋转臂
Schneider Electric - Industry Business – Machine Solutions – Success Stories
1
Customer Introduction 客户介绍
Solution Architecture 施耐德方案架构
• 工作性能描述: 此机型的速度为带负载60次每分钟.根据不同的物料可以编程变为不同的路径和轨迹
Schneider Electric - Industry Business – Machine Solutions – Success Stories

并联机器人原文知识分享

并联机器人原文Virtual Prototyping of a Parallel Robot actuated by Servo-Pneumatic Drives using ADAMS/ControlsWalter Kuhlbusch, Dr. Rüdiger Neumann, Festo AG & Co., Germany SummaryAdvanced pneumatic drives for servo-pneumatic positioning allow for new generations of handlings and robots. Especially parallel robots actuated by servo-pneumatic drives allow the realization of very fast pick and place tasks in 3-D space. The design of those machines requires a virtual prototyping method called the mechatronic design [ 1]. The most suitable software tools are ADAMS for mechanics and Matlab/Simulink for drives and controllers. To analyze the overall behavior the co-simulation using ADAMS/Controls is applied. The combination of these powerful simulation tools guarantees a fast and effective design of new machines.1. IntroductionFesto is a supplier for pneumatic components and controls in industrial automation.The utilization of pneumatic drives is wide spread in industry when working in open loop control. It’s l imited however, when it comes to multipoint movement or path control. The development has been driven to servo-pneumatic drives that include closed loop control. Festo servo-pneumatic axes are quite accurate, thus they can be employed as drives for sophisticated tasks in robotics. The special advantage of these drives is the low initial cost in comparison to electrical and hydraulic drive systems. Servo-pneumatic driven parallel robots are new systems with high potentials in applications. The dynamical performance meets the increasing requirements to reduce the cycle times.One goal is the creation and optimization of pneumatic driven multi-axes robots. This allows us to support our customers, and of course to create new standard handlings and robots (Fig. 1).The complexity of parallel robots requires the use of virtual prototyping methods.Fig. 1. Prototypes of servo-pneumatic driven multi-axes machinesPreferred applications are fast multipoint positioning tasks in 3-D space. Free programmable stops allow a flexible employment of the machine. The point to point (ptp) accuracy is about 0.5 mm. The continuous path control guarantees collision free movement along a trajectory.1.1. Why parallel robots?The main benefits using parallel instead of serial kinematics is shown in Fig. 2.Fig. 2. Benefits of robots with parallel kinematicsHigh dynamical performance is achieved due to the low moved masses. While in serial robots the first axis has to move all the following axes, the axes of a parallel robot can share the mass of the workpiece. Furthermore serial axes are stressed by torques and bending moments which reduces the stiffness. Due to the closed kinematics the movements of parallel robots are vibration free for which the accuracy is improved. Finally the modular concept allows a cost-effective production of the mechanical parts. On the other hand there is the higher expense related to the control.1.2. Why Pneumatic Drives?The advantages of servo-pneumatic drives are:direct drives→high accelerating powercompact (especially rodless cylinders with integrated guidance)robust and reliablecost-effectiveDirect drives imply a high acceleration power due to the low equivalent mass in relation to the drive force. With pneumatic drives the relationship is particularly favorable. Festo has already built up some system solutions, predominantly parallel robots (see Fig. 1), to demonstrate the technical potential of servo-pneumatics. Which performance can be reached is shown in Fig. 3. This prototype is equipped with an advanced model based controller that makes use of the computed torque method [ 3].Fig. 3. Performance of the Tripod2. Design MethodThe system design, where several engineering disciplines are involved in, requires a holistic approach. This method is the so-called mechatronic design. The components of a mechatronic system are the mechanical supporting structure, the servo drives as well as the control. All these components are mapped into the computer and optimized with respect to the mutual interaction. This procedure can be used to analyze and improve existing systems as well as to create new systems. The two main steps of the mechatronic design are first building models in each discipline, and secondly the analysis and synthesis of the whole system. These steps are done in a cycle for the optimization.The modeling can be carried out in two ways: Either you apply one tool to build up models in all disciplines, but with restrictions. The other way is to use powerful tools in each discipline and to analyze the whole system via co-simulation. In this case you have to consider some specials of the solving method like communication step size or direct feedthrough behavior.2.1. Why Co-Simulation?Co-simulation is used because of the powerful tools, each specialized in its own discipline. ADAMS is an excellent tool for the mechanical part and Matlab/Simulink is the suitable tool for controller development and simulation of pneumatics.The behavior of the mechanical part is modeled at best usingADAMS/View. The advantages of ADAMS are:fast physically modeling of rigid and elastic bodiesextensive features for parameterizationanimation of simulation resultssolving inverse kinematics by “general point motion”visualization of eigenmodes (ADAMS/LINEAR)export of linear models (A,B,C,D)A big advantage is the automatic calculation of the direct and inverse kinematics. The direct kinematics of parallel structures often cannot be solved analytically. Furthermore different kinematics can be compared to each other very easily when you define a trajectory of the end-effector via “general point motion”.Applying these two software tools guarantees a high flexibility regarding the design of new systems. It is very important to analyze the closed loop behavior at an early stage. This makes a big difference between the mechatronic design and the conventional design. Furthermore the visualization of the mechanical system makes the discussion within a team very easy.2.2. RestrictionsA disadvantage is that the model of the mechanics is purely numerically available. However some symbolic code of the mechanical system is needed for the control hardware when the system becomes realized. In general we have to derive the equations of the inverse kinematics, which are used in the feed forward control. For specific robot types a controller with decoupling structure is necessary in order to fulfill the requirements. Then the symbolic code of the dynamics is needed. For this we have to pull up further tools to complete the task.2.3. What has to be analyzed?For the design of new robots it is important to know about the effect on the system stability and accuracy. The main properties that influence stability and accuracy are opposed in Table 1 for different kinematical structures.Table 1: Properties of different kinematical configurationsWith respect to the control the cartesian type is the best one. But the main disadvantage of a serial robot compared with a parallel one is the lower dynamics and the lower stiffness (see Fig. 2).Depending on the requirements with regard to dynamics and accuracy different control approaches must be applied. As mentioned above we prefer to employ a standard controller SPC200 for a single axis. Due to the coupling of the axes the stability of the closed loop system must be checked.3. Model of the TripodThe model of the Tripod consists of three parts: the mechanics, the pneumatic drives, and the controller.3.1. Mechanics (ADAMS)We apply the so-called delta-kinematics which causes a purely translational movement of the tool center point (tcp). An additional rotary drive allows the orientation of the gripper in the horizontal plane. Together with the rotary drive the machine has four degrees of freedom.Fig. 4. Degrees of freedom and structure of the TripodThe tripod is modeled using rigid body parts what is often sufficient for the present type of parallel structure. The upper and lower plates are fixed to ground. The profile tubes are connected to these plates via fixed joints. Eachslider has one translational degree of freedom. Both ends of a rod are connected to the neighbored parts by universal joints. Including the rotary drive, the model verification results in four Gruebler counts and there are no redundant constraints. The model is parameterized in such a way that different kinematical configurations can be generated very easily by means of design variables. The most important parameters are the radiuses of the plates (see Fig. 4) and the distances to each other. For instance the following configurations can be achieved just by variation of these parameters or design variables.Fig. 5. Variation of kinematics by “design variables”3.2. Servo-Pneumatic Drives (Simulink)The models of the servo-pneumatic drives are developed by means of Matlab/Simulink. Depending on the requirements several controller models were developed. It is common to all that they are highly non-linear. Mainly the compressibility of air makes a more complex control system necessary. All controller models including the standard controller SPC200 are available asC-coded s-functions. This allows to use the same code in the simulation as well as on the target hardware.A survey of the control scheme is shown in Fig. 6. For this contribution it is important to know about the interface for the co-simulation. The calculated forces of the servo pneumatics are the inputs to the mechanics. The slider positions are the outputs of the mechanics. Detailed information on the controllers can be found in [ 2] and [ 3].Fig. 6. Control structure4. Analyzing the behavior of the whole systemWhen the modeling is done we can go on with the second step of the mechatronic design. In the following it is assumed that the SPC200 controller always controls the machine. The task is the analysis and synthesis of different parallel kinematics relative to stability, dynamics, and accuracy for a given workspace.Some studies, e.g. concerning the workspace, can be made exclusive using ADAMS. Others such as feedback analysis are carried out by means of co-simulation.The workspace can be determined by varying all drive positions in all combinations. After simulation the end-effector positions are traced using the feature “create tracespline”.Fig. 7. Drive motions for the workspace calculationThe data can be visualized in ADAMS or any other graphics tool. As an example the workspace of the Tripod configuration of Fig. 7 is represented in Fig. 8Fig. 8. Workspace of the Tripod (configuration as in Fig. 7) Measuring the velocity of the end-effector at the same time delivers the gear ratios of all drives over the workspace.To examine the behavior of the closed loop system ADAMS/Controls is used to couple ADAMS and Simulink. Before the model can be exported some inputs and outputs of the plant must be defined by state variables. The inputs of the Tripod are the drive forces. Though the controller makes only use of the drive position some additional signals are defined as outputs: The drive velocities are needed for solving the differential equations of the pressures in the pneumatics model. Furthermore we need the velocity of the tool center point to calculate the non-linear gear ratios. Finally the drive accelerations serve for the calculation of the equivalent moved masses. The whole system is shown in Fig. 9.Fig. 9. Model of the whole systemThe model of the mechanics is embedded in Simulink. ADAMS/Controls makes the interface available by means of s-function.The equivalent moved masses depend on the positions of drives. The non-linearity of the robot grows with the strength of this dependency. As shown in Table 1 with the parallel kinematics there is a medium strong coupling of the dynamics. This coupling is neglected, if we use the standard SPC200 controller. Nevertheless there is an influence on the stability of theclosed loop system. To initialize and parameterize this controller we need the following information from the mechanics model:equivalent moved mass of each drive (depends on slider positions)gravity forces in initial positionCoulomb and viscous frictionThe controller is designed for a single axis with a constant mass. Due to the position dependency of the equivalent moved masses of the robot we have to choose an average value for each drive. Unfortunately with ADAMS there is no easy way to calculate the equivalent moved masses along atrajectory. We tried to apply different methods such as dividing a drive force by its acceleration during a slow motion, but this method yielded not insatisfying results. The best method found is the linearization of the system.However this requires ADAMS/Linear. When we define the drive accelerations as plant outputs in ADAMS/Controls the direct feed through matrix D of the exported linear system delivers the mass matrix in the defined operating point as1)()(-⋅=q q D f MCorresponding to the three degrees of freedom of the rigid body system the size of the mass matrix M(q) is three by three. It depends on the vector of the generalized coordinates of the drives. The non-diagonal elements cause the coupling between the axes. The factor f depends on the units chosen for the inputs and outputs. Whenthe forces are given in [N] and the accelerations are given in [mm/s 2] f is 0.001.With a slider mass of 2 kg and an end-effector mass of 2 kg the massmatrix for the three positions shown in Fig. 10 are:The gravity forces can be calculated very easily by static simulation.Likewise it is easy to model the friction in ADAMS. Nevertheless theparameters can differ very strong from one application to another one.With the parameterized controller the stability should be checked inseveral operating points by means of eigenvalues and the dynamics of the closed loop system can be analyzed by means of frequency responses.Of course with a robust controller you can start with a simulation in time domain. This gives information about the accuracy and system limits. For this we need the references for the drives. For a reference trajectory of the tool center point ADAMS applying the “general point motion” can generate the drive positions.Fig. 10. Solving inverse kinematics by feature "general point motion"In the following the simulation results are presented for a tripod configuration shown in Fig. 10. The workspace of this machine is illustrated in Fig. 8.Fig. 11. Left: Trajectory of the tool center point. Right: Drive references and measures5. ConclusionThe coupling of the software tools ADAMS and Simulink via co-simulation is a powerful method of virtual prototyping. This method enables an efficient design and optimization of servo-pneumatic driven robots. Especially robots with parallel kinematics can be analyzed very fast using ADAMS. Due to the potential of the linear analysis the use of ADAMS/Linear is meaningful. Particularly with controlled systems the linear analysis is required.Literature[ 1] Kuhlbusch, W., Moritz, W., Lückel, J., Toepper, St., and Scharfeld, F.: T RI P LANAR - A New Process-Machine Type Developed by Means of Mechatronic Design. Proceedings of the 3rd International Heinz Nixdorf Symposium on Mechatronics and Advanced Motion Control, Paderborn, Germany, 1999.[ 2] Neumann, R., Göttert, M. Ohmer, M.: Servopneumatik – eine alternative Antriebstechnik für Roboter, Robotik 2002, 19-20. Juni in Ludwigsburg, Germany, 2002, VDI-Bericht Nr. 1679 p. 537-544.[ 3] Neumann, R., Leyser, J., Post, P.: Simulationsgestützte Entwicklung eines servopneumatisch angetriebenen Parallelroboters. TagungsbandSIM2000 – Simulation im Maschinenbau, Dresden, Germany, 2000, p. 519-536.。

并联机器人-课件PPTb第1章并联机器人概述

1.1.5 并联机器人的特点
6）完全对称的并联机构具有较好的各向同性，也使完全对称的并联机器人具有较好的各向同性。
7）并联机构的各运动支链的结构相同时，有利于并联机器人的制造。
8）在位置求解上，并联机器人的运动反解容易，运动正解困难，这有利于并联机器人的控制。
9）并联机构的使用寿命长。
1.2 并联机器人的分类
构件是机械系统中能够进行独立运动的单元体。在并联机构中，刚性构件主要是连杆，弹性或柔性构件主要是柔索。
运动副是指两构件既保持接触又有相对运动的活动联接。在并联机构中，运动副有转动副、移动副、螺旋副、圆柱副、虎克铰和球面副等，多为面和面接触的低副。在机械工程中，通常又称这些运动副为关节或者铰链。
(3) 并联机构的类型
图1-3 2-PRR的2自由度并联机构图1-4 3-RPS的3自由度并联机构
(3) 并联机构的类型
图1-5 4-UPU的4自由度并联机构
图1-6 3-5R的5自由度并联机构
(3) 并联机构的类型
图1-7 6-UPU的6自由度并联机构图1-8 4-SPS/S的3自由度冗余驱动并联机构
混联机器人
五自由度混联机器人
混联机器人
五自由度混联机器人
1.2.4 按并联机器人的连杆的刚度分类
按并联机器人的连杆的刚度，并联机器人可以分为刚性和柔性并联机器人。
刚性连杆的并联机器人为刚性并联机器人。刚性并联机器人的连杆由刚性的杆件组成，刚性的杆件能受拉力和压力，变形量小，可使并联机器人有高的精度。刚性并联机器人的运动支链主要是液压缸、直线电机、滚珠丝杠和普通刚性杆，支撑或拉动平台。
例：三D打印并联机器人
汽车纵横双向驻车坡度角检测并联机器人

并联机器人综述论文

并联机器人综述论文院系：聊城大学东昌学院机电工程系专业：机械设计制造及其自动化班级：10本二姓名：姜丽梅学号：20100020749并联机器人综述论文摘要并联机器人是一类全新的机器人,它具有刚度大、承载能力强、误差小、精度高、自重负荷比小、动力性能好、控制容易等一系列优点,在21世纪将有广阔的发展前景。

本文根据掌握的大量并联机器人文献，对非对称3平动3ＵＰＵ并联机器人在运动学、动力学、机构性能分析等方面的主要研究成果、进展进行了阐述，同时阐述了非对称3平动3ＵＰＵ并联机器人在国内外的发展状况以及并联机器人构型设计原则关键词平动 3自由度并联机器人一、课题国内外现状及研究的主要成果少自由度并联机器人由于其驱动元件少、造价低、结构紧凑而有较高的实用价值，更具有较好的应用前景，因此少自由度的并联机器人的设计理论的研究和应用领域的拓展成为并联机器人的研究热点之一。

研究少自由度并联机构最早的学者应属澳大利亚著名机构学教授 Hunt ,在1983年,他就列举了平面并联机构、空间三自由度3-rps并联机构，但对四，五自由度并联机构未作详细阐述。

在Hunt之后,不断有学者提出新的少自由度并联机构机型。

在少自由度并联机构机型的研究中,三维平移并联机构得到广泛的重视。

clavel提出了一种可实现纯平运动三自由度Delta 并联机器人,在Delta机构的支链中采用平行四边形机构约束动平台的3个转动自由度。

Tsai提出的Delta机构完全采用回转副，并通过转轴的偏移扩大了Delta机构的工作空间。

在 Tricept并联机床上采用的构型是由 Neumann发明的一种具有3个可控位置自由度的并联机构，该机构的突出特点是带有导向装置,采用3个内副驱动支链并由导向装置约束动平台。

Tsai 通过自由度分析提取支链的运动学特征,系统研究了并联机构的综合问题,特别研究了一类实现三自由度平动的并联机构。

Rasim Alizade于2004年提出基于平台类型和联接平台的形式和类型进行分类的一种并联机构的结构综合和分类的新方法和公式,并综合出具有单平台和多平台的纯并联和串并联复联机构.我国燕山大学的黄真教授及其团队除了研制出解耦微型6维力传感器和微动机械，设计出一种新的高精度的机构方案外,还率先对少自由度并联机器人的基础理静刚度和精度.上海交大的高峰教授2002年运用复合副的概念来组合已知自由度数和自由度类型的支链,通过支链输出杆特殊的Plucker坐标来综合2-自由度的机器人。

并联机器人论文并联机器人位置反解工作空间传动性能尺度综合解读

并联机器人论文：三自由度并联机器人工作空间研究【中文摘要】本文对一种新型的3-RRRT并联机器人位置反解、工作空间、机构综合等方面进行了比较深入的研究,并运用MATLAB进行运动仿真。

具体内容为：对新型3-RRRT并联机器人进行了自由度进行分析,采用空间矢量法建立了3-RRRT并联机器人的位置方程,进行了反解求解和分析。

通过空间点判别条件,求取3-RRRT并联机器人的工作空间,对工作空间的各种截面进行分析,为后续的机构综合奠定基础,应用MATLAB软件对工作空间进行数值仿真。

通过位置分析,建立了3-RRRT并联机器人速度输入、输出方程,构造出机器人雅可比矩阵,从而得到传动性能评价指标的表达式。

以全域条件数为衡量指标,对3-RRRT并联机器人进行结构参数优化设计【英文摘要】In this dissertation, a new3-RRRT parallel manipulator was studied through MATLAB simulation in many fields, such as anti-solution, workspace and dimensional synthesis. The details are as follows:The freedom of the new type of 3-RRRT parallel manipulator was analysed, and a position equation with space-vector method established to solve and analysis of anti-solution. According to condition differentiation of the points, cquired the working space, a variety analysis of cross-section and A Numerical Simul...【关键词】并联机器人位置反解工作空间传动性能尺度综合【英文关键词】parallel manipulator position analysis workspace transmission performance dimensional synthesis【索购全文】联系Q1：138113721 Q2：139938848【目录】三自由度并联机器人工作空间研究摘要5-6Abstract6第一章绪论9-19 1.1 机器人的发展及应用9-13 1.1.1 机器人研究的意义9-10 1.1.2 机器人的产生和发展10-11 1.1.3 机器人的定义和分类11 1.1.4 国内外机器人发展现状及应用11-13 1.2 并联机器人的发展及应用13-17 1.2.1 并联机器人的起源13 1.2.2 并联机器人的特点13-14 1.2.3 并联机器人的应用研究现状14-17 1.3 论文的选题意义和主要研究内容17-19第二章三自由度并联机器人的位置分析19-30 2.1 引言19-20 2.2 三自由度并联机器人的机构分析20-30 2.2.1 三自由度并联机器人的机构组成20 2.2.2 3-RRRT并联机器人的自由度20-21 2.2.3 三自由度并联机器人的位置分析21-28 2.2.4 Matlab仿真28 2.2.5 对仿真结果进行理论分析28-30第三章三自由度并联机器人工作空间分析30-47 3.1 引言30-31 3.1.1 并联机器人工作空间研究的概述30-31 3.2 工作空间的影响因素31 3.2.1 虚拟杆长约束31 3.2.2 运动副转角约束31 3.2.3 奇异性约束31 3.2.4 杆件的尺寸干涉31 3.3 工作空间点判别的条件31-40 3.4 工作空间分析40-47 3.4.1 工作空间的搜索算法40 3.4.2 工作空间的搜索条件40-47第四章基于传动性能和工作空间3-RRRT并联机器人参数优化47-61 4.1 引言47 4.2 工作空间的衡量方法47-49 4.2.1 工作空间体积47-48 4.2.2 有效圆柱体积48 4.2.3 有效工作空间体积48-49 4.3 运动学性能分析49-50 4.4. 全域性能指标50-53 4.5 机构综合53-60 4.5.1 各构件尺寸对工作空间和全域条件数的影响53-57 4.5.2 3-RRRT并联机器人结构参数优化57-59 4.5.3 在圆柱体工作空间内进行机构综合59-60 4.6 本章小结60-61第五章结论与展望61-62 5.1 总结61 5.2 展望61-62参考文献62-67攻读硕士学位期间参与的科研项目及发表的学术论文67-68发表的论文67参与的科研项目67-68致谢68。

课程案例8-并联机器人

职业教育机电一体化专业教学资源库课程案例
课程名称：工业机器人调试
编制人：
邮箱：
电话：
编制时间：
编制单位：南京工业职业技术学院
《工业机器人调试》课程案例
工业机器人搬运手抓应用
1.课程案例基本信息
课程案例名称并联机器人应用
课程案例编号
关键词并联
对应知识点工业机器人码垛、搬运等
2.课程案例
并联机器人也称作并联机构（Parallel Mechanism，简称PM），可以定义为动平台和定平台通过至少两个独立的运动链相连接，机构具有两个或两个以上自由度，且以并联方式驱动的一种闭环机构。

图1
图1中展示了并联机器人，并联机构的出现，扩大了机器人的应用范围。

随着并联机器人研究的不断深入，其应用领域也越来越广阔。

它主要应用在：（1）运动模拟器、
（2）并联机床、（3）微操作机器人、（4）医用机器人、（5）操作器、（6）包装等。

并联机器人的应用程序调查--中英文翻译

毕业设计外文翻译院（系）机电信息系专业机械设计制造及其自动化外文出处Parallel Manipulators Applications—A Survey （英文原文自己可以通过学校的数据库（知网）下载)有英文原文，加我Q1985639755附件 1. 原文 2. 译文2013年3月并联机器人的应用程序——一项调查Y. D. Patel1*, P. M. George21Department of Mechanical Engineering, A. D. Patel Institute of Technology, New Vallabh Vidyanagar, India2Department of Mechanical Engineering, Birla Vishvakarma Mahavidyalaya Engineering College, Vallabh Vidyanagar, IndiaEmail: *yash523@Received February 9, 2012; revised March 25, 2012; accepted April 2, 2012摘要本文提出了串行和并行机器人之间的比较。

一天，双杠 lel 机械手在各个领域中的应用程序是变得明显和增长率也迅速加以利用精密制造，医疗科学的视野和空间探索设备中。

并联机器人可以定义作为其末端链接到该基地由几个独立运动链的闭环运动学链机制。

随函附上介绍各种并联机器人的分类。

纸张的首要重点是通过来实现并联机器人产业、空间、医学科学或商业用途的申请，所需精度定位在高速度的空间机械臂。

关键词：并联机械手；六足；可重构并联机器人；三角洲机器人1.导言并联机器人是广受欢迎最近即使常规串联机器人拥有大型工作区和灵巧的操纵性。

与串行的一个基本问题是他们的悬臂结构使它们易受弯曲在高负载和vi 型压电高速度导致缺乏精度和许多其他问题。

在此文件中，串行一个并联机器人优势进行比较。

并联机器人

School of Mechanical Engineering
航天器对接口
School of Mechanical Engineering
05
承载运动
移动重载装置模型
School of Mechanical Engineering
06
海上钻井平台
海上钻井平台模型
School of Mechanical Engineering
四自由度并联机构
Pierrot和Company，1999年提出四自由度 H4并联机构在1999年,Rolland年提出两种用于物料搬运的四自由度并联机构：Kanuk和Manta 在2000年,黄真和赵铁石综合处第一种对称的四自由度4-URU并联机构，可实现三个移动自由度和一个绕Z轴的转动自由
School of Mechanical Engineering
六自由度并联机构
在1999年,Park与Lee年提出一种机构复杂的双层五自由度并联机构 ustad提出一种基于两个并联机构的五自由度混合型结构在2001年,Jin综合出具有三个移动自由度和两个转动自由度的非对称五自由度并联机构
School of Mechanical Engineering
在原有DELTA机器人的分支运动链中加装了一个和动平台垂直的转动副，从而在DEITA机器人原有的三个移动自由度外，又获得了一个转动自由度。
H4四自由度并联机构
Kanuk四自由度并联机构
School of Mechanical Engineering
School of Mechanical Engineering
Delta三自由度并联机构
视频播放
School of Mechanical Engineering

并联机器人-文献综述

并联机器人综述引言并联机器人是一类全新的机器人,它具有刚度大、承载能力强、误差小、精度高、自重负荷比小、动力性能好、控制容易等一系列优点,在21世纪将有广阔的发展前景。

本文根据掌握的大量并联机器人文献,对其分类和应用做了简要分析和概括，并对其在运动学、动力学、机构性能分析等方面的主要研究成果、进展以及尚未解决的问题进行了阐述。

第一章并联机构的发展概况1.1并联机构的特点并联机构是一种闭环机构,其动平台或称末端执行器通过至少2个独立的运动链与机架相联接,必备的要素如下:①末端执行器必须具有运动自由度;②这种末端执行器通过几个相互关联的运动链或分支与机架相联接;③每个分支或运动链由惟一的移动副或转动副驱动。

与传统的串联机构相比，并联机构的零部件数目较串联构造平台大幅减少，主要由滚珠丝杠、伸缩杆件、滑块构件、虎克铰、球铰、伺服电机等通用组件组成。

这些通用组件可由专门厂家生产，因而其制造和库存备件成本比相同功能的传统机构低得多，容易组装和模块化。

除了在结构上的优点，并联机构在实际应用中更是有串联机构不可比拟的优势。

其主要优点如下：（1）刚度质量比大。

因采用并联闭环杆系,杆系理论上只承受拉、压载荷,是典型的二力杆,并且多杆受力，使得传动机构具有很高的承载强度。

（2）动态性能优越。

运动部件质量轻，惯性低,可有效改善伺服控制器的动态性能,使动平台获得很高的进给速度与加速度,适于高速数控作业。

（3）运动精度高。

这是与传统串联机构相比而言的,传统串联机构的加工误差是各个关节的误差积累,而并联机构各个关节的误差可以相互抵消、相互弥补，因此，并联机构是未来机床的发展方向。

（4）多功能灵活性强。

可构成形式多样的布局和自由度组合,在动平台上安装刀具进行多坐标铣、磨、钻、特种曲面加工等，也可安装夹具进行复杂的空间装配，适应性强，是柔性化的理想机构。

（5）使用寿命长。

由于受力结构合理，运动部件磨损小，且没有导轨，不存在铁屑或冷却液进入导轨内部而导致其划伤、磨损或锈蚀现象。

并联机器人文献综述

并联机器人文献综述1、引言人类千百年来对器械自动化的追求，促使了机器人的产生和发展。

自从 1961 年美国推出第一台工业机器人以来，机器人得到了迅速的发展。

广泛应用于工业各部门以及服务、医疗、卫生、娱乐等许多方面，对人类的生活产生了深远的影响。

现代所说的机器人多指工业机器人，大都是由基座、腰部（肩部）、大臂、小臂、腕部和手部构成，大臂小臂以串联形式连接，因而也称为串联机器人，目前关于机器人的研究大部分集中于这一领域。

就在串联机器人蓬勃发展的时候，又出现了一类全新的机器人——并联机器人。

它作为串联式机器人强有力的补充，扩大了整个机器人的应用范围，引起机器人学理论界和工程界的广泛关注，成为机器人研究的主要研究热点之一。

并联机器人作为一种全新的机器人，它具有刚度大、承载能力强、误差小、精度高、动力性能好等一系列优点，并联六自由度机器人在许多行业有着非常好的应用前景，其特殊结构给机器人带来许多其它机器人不具备的优点。

并联机器人是一种闭环机构，导致了其运动学和工作空间分析较为困难，同时也让机器人的精确控制变得特别困难。

机器人运动时每个液压缸上分配的负载是变化的，因此每个液压伺服回路的受力、频率等系统参数也是变化的，常用的控制算法很难实现系统的精确控制。

因此，对并联机器人的理论控制的研究对并联机器人的控制精度和应用推广有着重要的意义。

2、国内研究现状最近几十年，国内外学者对并联机器人的特点、机构学、运动学方面进行了广泛、深入的研究，并且对这方面取得的成果进行了详细的概括和总结。

但是,并联机器人作为一个结构复杂、多变量、多自由度、多参数耦合的非线性系统,其控制策略、控制方法的研究极其复杂。

最初设计控制系统时，大多把并联机器人的各个分支当作完全独立的系统来进行控制,控制策略为传统的PID控制，控制效果很不理想。

随着控制理论的发展，新的控制方法不断涌现，如智能控制"鲁棒控制"自适应控制等，并联机器人的控制也得到了迅速发展。

并联机器人多目标协同智能控制

多目标协同智能控
02
制理论
协同控制理论
协同控制理论概述
协同控制理论是一种强调多机器人或多机器系统通过相互协作以实现共同目标的控制理论。它着重于解决复杂任务，如分担工作负载，增加工作效率，提高灵活性等。
协同控制理论的核心概念
协同控制理论的核心概念包括任务分配、信息共享、协同决策等。这些概念旨在实现多机器人或多机器系统的最优协调和最佳性能。
混合智能控制
结合传统控制方法与人工智能技术，实现控制策略的灵活性和鲁棒性。
可视化与优化
通过可视化技术和优化算法，对并联机器人的运动过程进行优化，提高作业效率和精度。
跨学科合作与创新
控制科学与工程
结合控制理论与方法，研究并联机器人的运动控制策略，提高系统的稳定性和鲁棒性。
计算机科学与技术
利用计算机科学中的算法和计算技术，实现高效的感知、学习和决策过程。
实现生产过程的自动化和智能化
并联机器人的出现使得生产过程可以更加高效地进行，提高了生产效率和产品质量。
满足高精度、高强度、高危险性的生产需求
并联机器人的高精度和高强度特性使得在一些高危险性的环境中也能够实现生产过程的自动化和智能化。
推动工业技术的发展
并联机器人的研究和应用不仅推动了工业技术的发展，也为其他领域的研究和应用提供了新的思路和方法。
智能控制理论概述
智能控制理论是一种以人工智能为基础的控制理论，它强调机器学习、模式识别、神经网络等技术在控制系统中的应用。
智能控制理论的应用
在并联机器人控制中，智能控制理论可用于实现自适应控制、预测控制、模糊控制等先进的控制策略。
多目标协同智能控制的应用
并联机器人的应用